JPS6088089A - Liquefaction of coal - Google Patents

Abstract

PURPOSE:To improve the conversion and the yield of liquefied oil and to reduce the yield of asphaltene, by liquefying coal at a high temp. under high pressure in the presence of a catalyst composed of finely divided natural pyrite. CONSTITUTION:A solvent such as creosote oil or naphtha is mixed with pulverized coal (e.g. anthracite or brown coal) having a particle size passing through a 50-mesh sieve in a weight ratio of 1:1-5:1. At least 2wt% (based on the quantity of coal) finely divided natural pyrite having a particle size passing through a 500-mesh sieve is added as a catalyst to the mixture. The mixture is then subjected to a liquefaction reaction in the presence of hydrogen at 300-550 deg.C under a pressure of 50-400kg/cm<2> for 10-120min.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coal liquefaction method, more specifically, to improve the conversion rate and liquefied oil yield, and to improve the liquefied oil yield by using finely ground natural pyrite as a catalyst, which is inexpensive and can be supplied in large quantities. This invention relates to a coal liquefaction method designed to reduce asphaltene yield.

In recent years, with the depletion of petroleum resources and the rise in petroleum prices, the need for alternative energy has come to be recognized, and many studies have been conducted on the liquefaction reaction of coal as one of the alternative energies.

This coal liquefaction is usually carried out at high temperature and pressure in the presence of a catalyst, with the addition of hydrogen to increase the hydrogen atom/carbon atomic ratio. In this coal liquefaction, it is necessary from an economical point of view to obtain a good conversion rate and liquefied oil yield.
It is still important for the operation of coal liquefaction to reduce the amount of asphaltene contained in liquefied oil. If the amount of this asphaltene substance is large, the overall viscosity becomes high, which tends to cause problems in the process, and it also increases the viscosity in the distillation process.

The migration of light fractions to the bottom side increases, and furthermore, the separation in the solid-liquid separation step, which is essential for coal liquefaction, is not sharp.

By the way, if natural pyrite, which is inexpensive and can be supplied in large quantities, can be used as a catalyst in coal liquefaction to improve the conversion rate and liquefied oil yield and reduce the asphaltene yield, it would be possible to improve the continuous coal liquefaction reactor. While enabling stable operations, it also reduces the cost of coal liquefied oil.
Moreover, it leads to effective use of resources. However, natural pyrite differs in its production area, mining period, degree of ore beneficiation, iron and sulfur content, atomic ratio S/Fe, silica and alumina content, alkali metal and alkaline earth metal content, etc. It is known that the physical properties are also different;
S), the catalytic activity of the natural pyrite for coal liquefaction is
Production area and mining period (Alθxander.

B,F,ancl'Andetson,R,P,,Pr.
eprints Am, Ohem.

Soc, Div, Fuel Ohem,, 27(2)
, 18 (1982):] Differences in chemical properties (Montan
o, P, A, and Granoff.

B., Fuel, s9.2+4 (1980)) had different practical problems.

In view of these circumstances, the inventors of the present invention have conducted extensive research into the effective use of natural pyrite as a catalyst for coal liquefaction, and as a result, they have found that it is possible to use natural pyrite after finely pulverizing it. , the conversion rate and liquefied oil yield are improved, the asphaltene yield is reduced, and the effects of differences in production area and mining period, in other words, differences in chemical properties and surface properties, on the catalytic activity of natural pyrite are reduced. We have found that the problem can be reduced, and based on this knowledge, we have completed the present invention.

That is, the present invention provides a method for liquefying coal, which is characterized by using finely ground natural pyrite as a catalyst in liquefying coal under high temperature and high pressure.

The raw materials used in the method of the present invention include, for example, pulverized coal such as anthracite, bituminous coal, sub-bituminous coal, brown coal, lignite, and mixtures thereof, and these are usually used after being ground to a particle size of 50 mesh or less.

In the method of the present invention, a solvent is usually used.

Examples of this solvent include liquefied coal oil, coal tar fractions such as creosote oil and anthracene oil, petroleum fractions such as heavy oil, light oil, kerosene, naphtha, and heavy oil, and aromatic hydrocarbons such as naphthalene and tetralin. Examples include, but
Among these, liquefied coal oil is preferred.

They may have different chemical properties, surface properties, etc., but they must be finely pulverized before use. The degree of fine pulverization is below 500 mesh.
It is preferable to grind the powder to a particle size of 1000 mesh or less.

In addition, the amount of catalyst used depends on the coal, solvent, particle size of coal and catalyst used in the liquefaction reaction, preferably at a temperature of 300 to 550'C and 50 to 400 kg.
/cr! The liquefaction reaction is carried out under pressurized conditions. The reaction time is usually about 10-120 minutes.

The liquefied oil thus obtained can be made into a product through solid-liquid separation and distillation steps.

In the coal liquefaction method of the present invention, natural pyrite, which is inexpensive and can be supplied in large quantities, can be used as a catalyst regardless of the history of the production area, etc., thereby improving the conversion rate and liquefied oil yield, and improving the asphaltene yield. rate is reduced. Therefore, the method of the present invention enables more stable operation of a continuous coal liquefaction reactor, is economical, and leads to effective use of resources.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 50p of Pacific coal crushed to pass 100 mesh,
io coal liquefied oil 1007 and natural pyrite having different production areas and chemical properties as shown in Table 1.

The pulverized material 1 to pass through the mesh or the 5y- to pulverized material to pass through 1000 meshes was placed in a 500 mA shaking autoclave. 5. Next, hydrogen gas was filled to 200 to 9/c4, and heated to 4oO℃ for 60 minutes. Made it react. After the reaction is complete, cool the autoclave.

Gas and oil components were analyzed and the results shown in Table 2 were obtained.

As can be seen from Table 2, for any type of natural pyrite, those that pass 1000 meshes show a higher conversion rate than those that pass 100 meshes, and regardless of the type of natural pyrite, It is around %.

These conversion rates were directly determined using a red mud-sulfur catalyst, as reported by Shin Yokoyama et al. at the 19th Coal Science Conference sponsored by Japan Fuel Association, held in Tokyo from October 26 to 29, 1982. This is higher than the conversion rate (64', 3% by weight) in the case of coal liquefaction, and is almost equivalent to the conversion rate (76.7% by weight) of highly active synthetic pyrite prepared for coal liquefaction.

Regarding the reaction product distribution, the asphaltene yield decreases due to fine pulverization, and the liquefied oil yield (oil 1 + oil 2
) is increasing. Furthermore, the hydrogen consumption rate is also increasing in the case of fine pulverization.

Example 2 Using natural pyrite as a catalyst, a coal liquefaction experiment was conducted under the reaction conditions shown in Table 3 using a coal liquefaction continuous test device with a capacity of 0.1 ton/day and having a configuration similar to that of an industrial process. .

The sample charcoal used for this was Pacific charcoal, and it was also a charcoal sample. The results are shown in Table 3.

For comparison, Table 3 also shows the results of an experiment using red mud + S as a catalyst.

Table 3 As can be seen from Table 3, pulverizing natural pyrite increases its catalytic activity under both reaction pressures of 200 Kg/ca and 300 K9/crab.
It has been confirmed that the catalyst exhibits an activity equivalent to that of the red clay-sulfur iron-based catalyst, which has traditionally been considered to have the highest activity.

Patent applicant: Director of the Agency of Industrial Science and Technology Hirobu Kawada Designated agent: Toshio Sato, Director of the Hokkaido Industrial Development and Testing Institute, Agency of Industrial Science and Technology

Claims (1)

[Claims] 1. A coal liquefaction method characterized by using pulverized natural pyrite as a catalyst for liquefying coal under high temperature and high pressure.